Recently there has been an increasing trend towards the incorporation of colored speckles into particulate laundry detergent compositions and other consumer products. Dyes and pigments have been widely used to produce colored speckles that serve aesthetic purposes only. Novel effects such as release of color into the wash water and hueing of fabrics, however, tend to require higher colorant loadings. There is, particularly at these higher colorant loadings, a fabric staining risk associated with dye and pigment use. Thus, the need exists for colored speckles for use in detergent compositions and other consumer products that can serve both an aesthetic purpose and also provide the novel effects of release of color and hueing of fabrics without staining the substrates that come into contact with the colored speckles.
Additionally, the inclusion of colored speckles in granulated laundry detergents presents the problem of bleeding or transferring onto the powdered detergent surrounding the speckle. This results in the base powder becoming colored, which is a highly undesirable effect. Thus, the need exists for colored speckles for use in detergent compositions which do not bleed or transfer to the surrounding base powder.
Attempts by others to include colored speckles in detergents include, for example, U.S. Pat. No. 4,097,418 to Rolfes. This patent discloses the use of colored speckles in granular detergent compositions. The colored speckles are comprised of a water soluble inorganic alkaline salt which acts as a carrier for the coloring agent. The coloring agent may be a water-soluble dye or a water-insoluble pigment. U.S. Pat. No. 6,541,437 to Mata et al. discloses the use of glassy phosphate particles as carriers for dyes and/or pigments. The colored particles may be added to a detergent formulation to aid in improving its cleaning performance.
Yet another example includes WO 2006/099964 A1 to Andrade et al. which discloses the use of a speckle granule comprised of a clay mineral carrier and a mica pigment. To increase the rate of dispersion of the granule in the wash liquor, this reference teaches the inclusion of a soluble builder salt, such as sodium tripolyphosphate, admixed with the clay in the granule. A water-soluble polymeric coating, such as polyvinyl alcohol, may also be added to the granule, to help prevent the mica from leaving the clay during storage and handling.
The problems associated with previous attempts by others to include colored speckles in detergents include fabric staining from the colorant used in the speckles and bleeding and transferring of the colorant to the surrounding detergent powder. There also exists a need for time controlled color release (e.g. release on demand or delayed release that may be optimized for long delay or short delay) into wash water from the speckles. The present disclosure addresses and overcomes these problems.
The colored speckles of the present disclosure are ideally suited for providing color to various other compositions including, but not limited to granular detergent compositions (such as laundry detergent compositions). The colored speckles may provide non-staining, aesthetically-pleasing features to textile substrates treated therewith. They also resist bleeding or transferring to the surrounding detergent composition. Furthermore, the colored speckles of the present disclosure provide controlled release of color, or other actives, from the salt or salt-containing carrier and provide desirable color to the wash water. For these reasons, and others that will be described herein, the present colored speckles represent a useful advance over the prior art.